In my limited experience (AKG K7XX, Fidelio X2, Beyerdynamic T70, HIFIMAN HE-400i), it is highly dependent on the headphone you're using and the type of game you're playing.
There are some pre-sets, called "profiles." I like to start with them, and tweak the sound as necessary. For warmer headphones, Scout Mode is very cool - it works like a charm with the X2. With the T70s, I used "First Person Shooter" mode, and it was literally painful. I fully expected my ears to bleed from the experience. I was fiddling with the HE-400is, and I couldn't get it to sound right.
After almost a year with it, I'm finally getting a handle on the sound I want for a given type of game.